Infants are happy with objects that can draw their attentions. Pacifiers contact infant's lips, thus becoming a very easy amusement. In many instances, sound and music may draw infant's attention. However, in some occasions which the environment is quiet, such as churches, airplanes and restaurants, toys that produce sound or music are not appropriate. Although earphones can provide individual music environment which avoid disturbing the others, infant's ears are just too small to use earphones. Also, using earphones for too long may impair their hearings.